Arctia caja (Linnaeus, 1758)


Arctia caja: Adult (S-Germany, Memmingen, 2017) [S] Arctia caja: Adult (S-Germany, Memmingen, 2017) [S] Arctia caja: Adult (S-Germany, Memmingen, 2017) [S] Arctia caja: Adult (e.l. eastern Swabian Alb, Southern Germany) [S] Arctia caja: Adult (e.l. eastern Swabian Alb, Southern Germany) [S] Arctia caja: Adult in resting posture [S] Arctia caja: Male [S] Arctia caja: Male [S] Arctia caja: Female [S] Arctia caja: Female [S] Arctia caja: Adult in resting posture [S] Arctia caja: Adult, daunting position [S] Arctia caja: Adult [M] Arctia caja: Female after oviposition in 3 m height on birch (S-Germany, Allgäu, August 2020) [N] Arctia caja: Female after oviposition in 3 m height on birch (S-Germany, Allgäu, August 2020) [N] Arctia caja: Eggs on birch (S-Germany, Allgäu, August 2020) [M] Arctia caja: Eggs on birch (S-Germany, Allgäu, August 2020) [M] Arctia caja: Eggs on birch (S-Germany, Allgäu, August 2020) [S] Arctia caja: Eggs prior to hatching on birch (S-Germany, Allgäu, August 2020) [S] Arctia caja: Eggs on the lower side of a Sambucus nigra leaf, found at the edge of a spruce forest (S-Germany, Memmingen, August 2014) [M] Arctia caja: Eggs (female had been disturbed by the observer, Memmingen, August 2013) [M] Arctia caja: L1-larva (Memmingen, August 2014) [S] Arctia caja: L1-larva (Memmingen, August 2014) [S] Arctia caja: L1-larva (Memmingen, August 2014) [S] Arctia caja: L1-larva (Memmingen, August 2014) [S] Arctia caja: Larva in the second instar [S] Arctia caja: Young larva in early autumn (Ostalb, September 2011) [M] Arctia caja: Young larva prior to hibernation (eastern Swabian Alb, Southern Germany) [M] Arctia caja: Young larva in the autumn (eastern Swabian Alb, Southern Germany) [M] Arctia caja: Young larva prior to hibernation (S-Germany, Memmingen, 02. November 2019) [S] Arctia caja: Young larva prior to hibernation (S-Germany, Memmingen, 02. November 2019) [S] Arctia caja: Young larva prior to hibernation (S-Germany, Memmingen, 02. November 2019) [S] Arctia caja: Young larva prior to hibernation (S-Germany, Memmingen, 02. November 2019) [S] Arctia caja: Young larva [M] Arctia caja: Young larva after hibernation [S] Arctia caja: Half-grown larva after hibernation (S-Germany, Memmingen, 2017) [S] Arctia caja: Half-grown larva after hibernation (S-Germany, Memmingen, 2017) [S] Arctia caja: Half-grown larva [N] Arctia caja: Half-grown larva (river Iller near Oberbinnwang, May 2013) [N] Arctia caja: Half-grown larva (eastern Swabian Alb, 2011) [S] Arctia caja: Half-grown larva [N] Arctia caja: Half-grown larva (eastern Swabian Alb, 2011) [S] Arctia caja: Half-grown larva [S] Arctia caja: Larva in penultimate instar [N] Arctia caja: Larva in the penultimate instar (S-Germany, Memmingen, 2017) [S] Arctia caja: Larva [S] Arctia caja: Larva [S] Arctia caja: Larva (NE-Germany, Müritz, late May 2013) [N] Arctia caja: Larva (NE-Germany, Müritz, late May 2013) [N] Arctia caja: Larva (eastern Swabian Alb, June 2013) [N] Arctia caja: Larva (S-Germany, Memmingen, 2017) [S] Arctia caja: Larva (S-Germany, Memmingen, 2017) [S] Arctia caja: Larva [M] Arctia caja: Larva [M] Arctia caja: Pupa [S] Arctia caja: Habitat in the herb rich embankments of a stream in the foreland of the eastern Swabian Alb in Germany in September 2011. Here I found regularly but accidently young larvae in the early autumn by beating the herbs (mostly Urtica dioica). [N] Arctia caja: Larval habitat on the eastern Swabian Alb: open places with Urtica in damp woodland (June 2013) [N]

Host plants:
The caterpillar lives polyphagous on herbs such as Urtica and low shrubs. Oviposition takes place often higher above ground on leaves of sallow and other woody plants, where the young caterpillars often live sociable in the first instar.

Habitat:
Arctia caja colonizes nearly all habitat types that are not entirely covered by dense forest and are not over-exploited such as tall herb communities, forest clearings and edges, clearcuts, borders of rivers, fens and alpine pastures up to about 1800m above sea level. It shows a certain preference for humid and cool habitats. In urban areas Arctia caja can be observed only rarely nowadays. The moths avoid very hot and dry, low growing habitats, but seems on the other hand to be able to settle nitrogen-rich Urtica stocks and also in quite grove-dominated sites.

Life cycle:
Oviposition takes most often place on lower sides of leaves, often in bushes or small trees. In the autumn the larva is commonly beaten out of the herb layer and from bushes. Hibernation takes place as a young caterpillar which is mature in June or July. The moths fly mostly from July to August.

Endangerment: regionally endangered or decreasing

Endangerment factors:
Arctia caja is locally declining significantly, but overall still not seriously threatened because of its ability to settle in nutrient-rich environments.

Remarks:
Arctia caja ranges from Spain across almost whole Europe until well into east Asia. It is also found in North America (holarctic distribution pattern).



Arctia aulica | Arctia dejeanii | Arctia festiva | Arctia flavia | Arctia lapponica | Arctia testudinaria | Arctia tigrina | Arctia villica